Method of making and adjusting deflection yoke

ABSTRACT

The core and deflection coils of a deflection yoke assembly for a color television cathode tube are initially assembled and mounted to provide for the relative fine adjustment of the core and deflection coils along at least the vertical axis and most desirably also along the horizontal axis. Separate screw adjusting means or the like, either permanently or temporarily affixed to the deflection yoke assembly, relatively adjusts the relative positions of the deflection coils and the core. The adjustment along the vertical axis is used to vary the red-green trace crossover of a cross-hatch video pattern at the 3 and 9 o&#39;&#39;clock positions of the cathode ray tube face to zero or a finite value. The adjustment along the horizontal axis is used to equalize or reduce to zero the red trace height of a cross-hatch video pattern at the 12 and 6 o&#39;&#39;clock positions of the cathode ray tube face.

United States Patent 1 1 McGlashan METHOD or MAKING AND ADJUSTlNG.DEFLECTION YOKE Inventor: Kenneth W. McGlashan, Laredo,

Related uLs. Application Data Division of Ser No. 284,370, Aug. 28,1972, Pat. No. 3,810,053,

US. Cl 29/25.l3, 178/7.8, 335/212, 324/158 R Int. Cl. H0lj 9/18 Field ofSearch 29/25.1 1, 25.13; 178/7.8, I 178/781; 335/210, 212, 213; 324/158R References Cited UNITED STATES PATENTS 5/1970 Mancini 29/2513 12/1971Massa l 335/210 1/1971 Chistensen 335/210 1 1 Oct. 29, 1974 PrimaryExaminer-R0y Lake Assistant Examiner-James W. Davie Attorney, Agent. orFirm-Wallenstein, Spangenberg, Hattis & Strampel [57] ABSTRACT The coreand deflection coils of a deflection yoke assembly for a colortelevision cathode tube are initially assembled and mounted to providefor the relative fine adjustment of the core and deflection coils alongat least the vertical axis and most desirably also along the horizontalaxis. Separate screw adjusting means or the like, either permanently ortemporarily affixed to the deflection yoke assembly, relatively adjuststhe relative positions of the deflection coils and the core. Theadjustment along the vertical axis is used to vary the red-green tracecrossover of a cross-hatch video pattern at the 3 and 9 oclock positionsof the cathode ray tube face to zero or a finite valueThe adjustmentalong the horizontal axis isused to equalize or reduce to zero the redtrace height of a cross-hatch video pattern at the 12 and 6 oclockpositions of the cathode ray tube face.

15 Claims, 13 Drawing Figures PATENTEDum-zs 1974 SHEET MI? 7 FIG. 1

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PATENTEDUBT-ZQ QM 3.3441306 SHEET E UF I I fields outside of the cathoderay BACKGROUND OF THE INVENTION This invention relates to deflectionyoke assemblies for color television cathode ray tubes and a method ofmarking and adjusting the same. 7

Color television cathode ray tubes are commonly provided with threejuxtaposed electron guns positioned either triangularly or in-line atthe base of the narrow neck of the cathode ray tube, so the cathodebeams generated by these electron guns assume substantially differentpositions within the various transverse cross sectional planes of thecathode ray tube until they reach a point at or near the phosphor coatedfront face of the cathode ray tube. The phosphor coatings on the frontface of the cathode ray tube are deposited as triads of phosphor dots,each dot of a triad responding to impingement thereon of a beam intendedto produce a different one of the three characteristic colors of red,blue or green. A perforated screen or mask spaced behind the phosphorcoated face forms beam screening areas for the various beams approachingthe same at different angles so that each beam, which generallyencompasses a number of groups of triad dots, passing through the samescreen apertures as the other beams will only strike the triad dot whichproduces the color assigned to the beam involved.

To produce deflection of the beams, a deflection yoke assembly ismounted around the neck of the cathode ray tube. The deflection yokeassembly conventionally used today has deflection coils carrying timevarying signals producing electron beam deflecting, vertically andhorizontally extending, magnetic fields within the portion of thecathode ray tube transversed by the said electron beams. In one form ofdeflection yoke assembly, vertically spaced coils on the top and bottomof the tube neck produce a vertically extending magnetic field whicheffects horizontal deflection of the beams, and horizontally spacedcoils on opposite sides of the tube neck produce a horizontallyextending magnetic fleldwhich effects vertical deflection of the beam. Acore snugly envelopes the outermost of these coils to provide a lowreluctance path for the magnetic tube.

To cause convergence of registration of the beams at or adjacent to thefront face of the cathode ray tube, there is commonly'provided bothelectromechanical and electronic means for effecting this result. Thus,a convergence yoke assembly is generally mounted around the neck of thecathode ray tube behind the deflection yoke assembly which convergenceyoke assembly is provided with individual. manual adjustments whichcommonly move permanent magnets for varying static magnetic fieldcomponents respectively in the paths of the red, green and blueproducing electron beams, so that the three beams converge intoregistration at the center of the cathode ray tube. Other mag- I neticfield adjusting units are also mounted on the neck of the cathode raytube referred to as purity and lateral blue adjusting units, further toinsure that each beam strikes its proper phosphor dot.

Contemporary deflection yoke assemblies do not produce linear magneticfields, that is, the flux lines (and equi-potential lines at rightangles thereto) are curved in order to produce pictures withoutundesirable distortions whichwould otherwise occur because the frontface of the cathode ray tubes is relatively flat and hence notequi-distant at all points from the electron guns referred to. As theelectron beams are deflected from the center of the front face of acathode ray tube, the intensity of the magnetic fields produced by thecurrent flowing through the horizontal or vertical coils of thedeflection yoke assembly become greater. in both the possibletriangularly and in-line related positioning of the electron guns asmanufactured today, the electron guns which generate the red and greenproducing electron beams occupy the same vertical position but differenthorizontal positions in the neck of the cathode ray tube. The beamsproduced by these cathode ray guns will, therefore, occupy differentpositions horizontally within the curved vertically extending magneticfield of the horizontal deflection coils and are accordingly deflectedto different extents thereby both horizontally and vertically because ofthe curved equi-potential lines referred to, and in degree proportionalto the intensity of the magnetic fields involved.

The curved horizontally extending equi-potential lines of the horizontaldeflection coils, in the absence of dynamic convergence signals derivedfrom the horizontal deflection current generator circuits and fed towindings forming part of the convergence yoke assembly, produce aprogressively greater deflection of, the red producing electron beamupwardly with respect to the green producing electron beam as thedistance of the beam to the right of center of the face of the cathoderay tube increases, and a progressively greater deflection of the redproducing electron beam downwardly with respect to the green producingelectron beam as the distance of the beam to the left of the center ofthe face of the cathode ray tube increases. Thus, assuming the greentrace as a reference trace which is approximately horizontal across theface of the cathode ray tube, the red trace crosses over the green traceso it occupies a position rotated counterclockwise of the green trace. Adivergence of the green and red traces of only one-thirty-two inches isreadily noticeable. Such crossing divergence between the horizontal redand green traces occuring at the horizontal center line of the cathoderay tube face is referred to as crossover" and the degree thereof ismeasured at the 3 and 9 oclock positions thereon. A similar crossingdivergence of the horizontal red and gree traces occurs above and belowthe horizontal center line of the cathode ray tube face for reasonsincluding those responsible for crossover at the horizontal center lineof the cathode ray tube face.

Divergence between the traces also occurs at all points spaced from thecenter point of the cathode ray tube face, among other reasons, becausethe focal or convergence points of the different beams occurs at pointsspaced progressively increasing distances from this face proceeding awayfrom the center point due to the aforesaid varying distances of theelectron guns to various points on the cathode ray tube face.

These various divergences between the traces are ultimately reduced tozero or to finite tolerable limits so that an acceptable color pictureis achieved. Where the deflection yoke assembly meets certainspecifications, this can generally be achieved by the feeding to thedeflection coils to vary the magnetic" fields affecting theelectronbeams as a function of beam deflection, to converge or'registerthe electron beamswhich would otherwise be out of registratioinprogressively increasing degrees as the beams are deflected further fromthe right or left of or up and down from the center of the cathode raytube face. To obtain the properly shaped dynamic convergencesignals alarge number of manual adjustments of different circuit variables arerequired to provide proper dynamic convergence of the horizontaland redtraces over the entire face of the cathode ray tube.

In testing the acceptability of a deflection-yoke assembly, it has beenheretofore common for the deflection yoke manufacturers to apply across-hatch video pattern to a standard test cathode ray tube used witha standard test receiver (both supplied by the television receivermanufacturer involved) to which tube the defl'ection yoke assembly to betested is applied. The cross-hatch video pattern comprises groups ofhorizontal and vertical red, green and blue traces in a grid-likepattern distributed over the face of the cathode ray tube. Inthe'absence of any dynamic convergence signals, a convergence unit alsomounted on the cathode ray tube is first adjusted to produce crossingwhite traces at the center ofthe cathode ray tube face. Then, inaccordance with the practice prior to the present invention, thevertical separation of the horizontal red and blue traces from thehorizontal green trace a the 12, 6, 3 and 9 oclock positions on thecathode ray tube face are measured along with the horizontal separationof the vertical red and blue traces from the vertical green tracesthereat. To ensure to the television receiver manufacturers satisfactionthat the dynamic convergence circuit adjustments in the televisionreceivers with which the deflection yoke assemblies are to be ultimatelyused will be operative to effect a proper final convergence (indicatedby crossing white traces at each of the trace crossover pointsinvolved), all of these measurements must fall within certain tolerancesspecified by the television receiver manufacturer involved. If thedeflection yoke assembly being tested produces trace divergenciesfallingwithin these tolerances, then the vertical separation of the horizontalred traces from the green horizontal traces are often measured in eachof the four corners of the cathode ray tube face to determine if theyfall within specified tolerances. A deflection yoke assembly which doesnot produce trace deflections within the limited trace divergenciesspecified has heretofore been rejected. Although, if a deflection yokeassembly passes the static tests referred to, it will normally pass atest where the traces are finally dynamically converged to produce thecrossing white traces at the various tests points involved, it is commonfor the deflection yoke manufacturer to make spot checks of thedeflection yoke assem-.

blies which passed the aforesaid static tests to determine whether thedynamic convergence circuit adjustments onthe standard test receiver canachieve the proper crossing white traces at these points on the cathoderay tube face andother intermediate points.

Because of the practical limits on the tolerances of the parts making upthe deflection yoke assemblies, a significant percentage of thedeflection yoke assemblies have often failed to meet specificationsresulting in a substantial loss of, materials, time and labor. If anassembled deflection yoke assembly was found to be deficient, it wasdiscarded ordis-assembled and the parts thereof combined with otherparts in the hope that the new combination would meet specifications.

Tolerances in the manufacutre of the cathode ray tube also introducedisplacements of the beam traces due, for example, to a slight rotationof the cathode ray guns in the cathode ray tubes from their desiredorientations. Thus, strict tolerances are also imposed on the cathoderay tube manufacturers so that with a standard test deflection yokeassembly supplied by the television receiver manufacturers for thepurposes of testing the cathode ray tubes, the displacements of the beamtraces thereon must fall within prescribed limits to ensure the receivermanufacturers that proper convergence of such traces can be achieved bythe dynamic convergence adjustments referred to.

Even with the strict tolerances presently imposed, the accepted degreeof variation in the beam trace displacements due to the tolerances inthe manufacture of deflection yoke assemblies and cathode ray tubes issuch that the person making the large number of ad'- justments of thedynamic convergence wave shaping circuits at the plant of the televisionreceiver manufacturer can'spend a considerable time in making thedifferent adjustments. This adjustment procedure can be simplified andthe reject ratio of the deflection yoke assembly and cathode ray tubemanufacturers significantly reduced if the deflection yoke assembliescould be made to produce identical or closely similar amounts of beamtrace displacements on the standard test cathode ray tube face. Thiswould also make'possible the increase of the tolerances permitted in themanufacture of the cathode ray tubes and the parts of the horizontaldynamic convergence wave shaping circuits or a simplification of thelatter circuits.

lt is one of the objects of the present invention to provide a method ofmanufacturing deflection yoke assemblies for color television cathoderay tubes which greatly reduces and in many cases eliminates any rejectsthereof. A related object of the invention is to provide a method ofadjusting a deflection yoke assembly for a color television cathode raytube so it can be quickly and easily placed in a condition where thebeam traces deflected thereby with cross-hatch producing signals appliedthereto and the cathode ray tube can be readily dynamically converged. Afurther related object of the invention is to provide a method ofadjusting a deflection yoke assembly for a color television cathode raytube wherein the assembly can be quickly and easily placed in acondition where the beam traces deflected thereby with cross-hatchproducing signals supplied thereto and the cathode ray tube are readilypositioned to provide a desired degree of crossover at the 3 and 9oclock positions of the cathode ray tube face and/ or red trace height(i.e. spacing of the horizontal red trace from the horizontal greentrace) at the 12 and 6 oclock positions of the cathode ray tube face.

SUMMARY 'OF THE INVENTION The various aspects of the present inventionresults from an unexpected discovery that the relative positions of thebeam traces of color cathode ray tubes, particularly the horizontal redand green trace crossover at the 3 and 9 oclock positions and/or thehorizontal red trace height at the 12 and 6 oclock positions of thecathode ray tube face, can be readily accurately varied between zero anda small finite value in one direction or the other by designing the coreand/or the vertical and/or horizontal deflection coils so that therelative vertical and/or horizontal positions thereof are adjustable,and varying the relative vertical and/or horizontal positions thereof toprovide the desired trace positions at these points. (Such adjustmentsare not possible on conventional deflection yoke assemblies since thecores thereof are designed to be unadjustable with respect to both thehorizontal and vertical deflection coils.) It has also been discoveredthat all of the various aforesaid previously taken divergencemeasurements need not be made to determine whether the deflection yokeassembly being tested has its optimum deflection producing parameters toensure that the crosshatch video pattern can be properly dynamicallyconverged. Thus, it was determined that if the 3 and 9 oclock red-greentrace crossover was adjusted to a correct value (which is generally, butnot necessarily in all cases, zero), the downward displacement of thehorizontal blue traces from the horizontal green trace at the 3 and 9oclock positions and the horizontal spacing between the vertical red andgreen traces at the 3 and 9 oclock positions would generallyautomatically be optimized (i.e., in their best positions to ensure aproper final dynamic convergence), making unnecessary the additionalmeasurement referred to.

This adjustment of the red-green trace crossover at the 3 and 9 oclockpositions of the cathode ray tube is achieved by varying the relativevertical position between the core and the deflection coils, and in mostcases could be the only adjustment needed to ensure that a cross-hatchpattern could be properly dynamically converged. However, for bestresults, another adjustment to be described is preferably carried out tooptimize all of the beam deflecting parameters of the deflection yokeassembly. Thus, in accordance with another aspect of the invention, as asecondary, though important, factor in optimizing the deflectionproducing parameters of the deflection yoke assembly, it was determinedthat if the spacing of the horizontal red trace from the horizontalgreen trace (i.e., red trace height) at the l2 and 6 oclock positionswere made ideally'zero or at least equal, the horizontal displacement ofvertical red traces from the vertical green traces and the verticaldisplacement of blue horizontal traces from the green horizontal tracesat the 12 and 6 o'clock positions are minimized. This red trace heightadjustment is achieved by varying the relative horizontal positionbetween the core and deflection coils. The two deflection yoke assemblyadjustments are most de sirably made by providing the assembly withseparate manual controls which respectively move the core relative tothe deflection coils along the vertical and horizontal axes thereof.

When the deflection yoke assembly need not be adjusted by the televisionreceiver manufacturer or by the serviceman, (this may be preferred sincethe adjustment made by the deflection yoke manufacturers can then bepermanently fixed by cementing the core and deflection coils togetherwhere vibrations and handling cannot disturb the adjustment), the meansfor adjusting the relative positioning of the core and horizontaldeflection coils need not be a permanent attachment to the deflectionyoke assembly to reduce the cost thereof. In such case, it is a meanswhich may be temporarily removably mounted upon each deflection yokeassembly and then removed for further use on another yoke after therelative positions of the core and deflection coils have been fixed asby cementing the same in their relative adjusted positions.

The adjustment of the horizontal spacing of the vertical blue tracesfrom the vertical green traces at the 3 and 9 oclock positions (referredto as blue width") has heretofore been effected by adjusting thevertical position of the entire deflection yoke assembly on the neck ofa cathode ray tube. However, such vertical adjustment does notperceptably vary the red-green trace crossover. What was not heretoforeappreciated is that a variation in the relative position between thecore and deflection coils of the deflection yoke assembly produces anyuseful result, such as a variation in red-green trace crossover. Sincethe core of a deflection yoke does not itself produce magnetic lines offorce but merely effects the magnetic reluctance of a magnetic pathoutside of the cathode ray tube, the moving of a core relative to thedeflection coils would not necessarily be expected to change therelative positions of the red-and green traces as above described.

Not only does the aforesaid adjustment of the deflection yoke assemblyeliminate the rejection of deflection yoke assemblies by the deflectionyoke manufacturers because of excessive trace divergences on the testcross-hatch pattern, but, unlike previous manufacturing techniques wherethere was a significant but acceptable variation in the red-green tracecrossover, it makes possible the manufacture of all deflection yokeassemblies producing near identical trace divergences so that greatertolerances in the angles of the electrode guns of the cathode ray tubesand the parts making up the dynamic convergence circuits can bespecified, if desired, and the effort needed to make the finaladjustments of the dynamic convergence circuits is significantlyreduced.

The above and other features, objects and advantages of the inventionwill become more apparent upon making reference to the specification tofollow, the claims and the drawings. wherein:

DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial sectional and partialelevational view of a deflection yoke assembly used in the method of thepresent invention;

FIG. 2 is a perspective view of a deflection yoke assembly adjustingstation where the deflection yoke assembly of FIG. 1 is adjusted tooptimize its beam deflection producing parameters in accordance with thepresent invention;

FIG. 3 is a perspective view of the cathode ray tube and deflection yokeassembly portion of the adjusting station of FIG. 2;

FIG. 4 is a plan view of the deflection yoke assembly adjusting fixtureforming one of the elements of the adjusting station shown in FIG. 2;

FIG. 5 is a sectional view through the deflection yoke assemblyadjusting fixture shown in FIG. 4, taken along section lines 5-5thereof, when the adjusting fixture is applied over the neck of acathode ray tube and temporarily receives a deflection yoke assemblyatthe adjustalong section line SA-SA thereof, when the adjusting fixtureis applied over the neck of a cathode ray tube and'te mporarily receivesa deflection yoke assembly at the adjusting station as shown in FIG. 2;I FIG. 6 is a view of a cross-hatch video pattern provided on the faceof the cathode ray tube at the adjusting station of FIG. '2 during thedeflection yoke assembly adjusting operation performed thereat;

FIG. 7A is a greatly-enlarged view of those portions of the cathode raytube face enclosed by dashed lines in F IG.J6, and includes arrows whichillustrates the effectonthe beam traces of a variation in the positionof the core relative to the deflection coils along the vertical axis ofthe deflection yoke assembly;

FIG. 7B is a view corresponding to FIG. 7A but including arrows whichillustrate the effect on the beam traces of a variation in the positionof the core relative to the deflection coils along the horizontal axisof the deflection yoke assembly; FIG. 8 is afragmentary sectional viewthrough the deflectionyoke assembly of FIG. .1 at the adjusting sta- 1tion shown in FIG. 2 after the adjustment thereof has been fixed byadhesively securingthe corein its final adjusted position;

7 FIG. '9 is a fragmentary. enlarged sectional view through thedeflection yoke assembly of FIG. 8, taken along section line 9-9thereof;

FIG. 10 is a side elevational view, partly in section, illustrating amodified form of deflection yoke assembly where the core adjusting meansis permanently affixed thereto; and n FIG. 11 is an exploded view of thecore adjusting means'forming a permanent attachment to the deflectionyoke assembly shown in FIG. 10.

' FIG. 1 'illustrates.a deflection yoke assembly 2 of the saddledeflection coil type presently used in most color television sets. Asthereshowmthe assembly includes a frame generally indicated by referencenumeral 4 made ofa suitablesynthetic plastic material. The frame 4, asillustrated, is made of two confronting'mirror-image parts 4a and 4b(FIG. 8) each including a generally forwardly flaring main body portion6 terminating in its front end in a radially outwardly extending frontannular wall or flange 8 joining an outer forwardly project- 12-12 ofthe confronting frame parts'4a-4b form a mounting panel upon whichvarious circuit-forming elements like 16 associated with deflection coilcircuits are soldered to terminal strips like '14 anchored to thecoplanar faces of the walls 12-12. A rear cover member 18 (preferablymade of a synthetic plastic material) is suitably releasably secured tothe walls 12--l2 in any well known manner. The cover member 18 has acentral opening l9 defined by an inwardly flexible cathode ray tubeengaging neck portion Zlwhich, as illustrated,

is anchored to the neck portion of a cathode ray ,tube by a clamp 20enveloping the fle'xibleneck portion 21 and having a tightening screw23.

I The frame 4 has securely anchored tothinner surface 29 of theforwardly flaring main body portion thereof a pair of vertically spacedhorizontal deflection coils 28a28b. A pair of horizontally spacedvertically spaced deflection coils30a-30b are closely but rotatablyadjustably mounted around ,the'outer surface 31- of the forwardlyflaring main body portion 6 of the frame 4. As is well known, currentflow through vertically spaced horizontal deflection coils 28a-28bgenerates a vertically extending magnetic field within thespaceenveloped thereby which effects'horizontal displacement of electronbeams, and currentflow through the horizontally spaced verticaldeflection coils 30a-30b generates a horizontally extending magneticfield within the spaced envelope thereby which effects verticaldisplacement of electron beams.

To provide a sufficiently high magnetic field strength for a givencurrent flow in the deflection coils, a low magnetic reluctance path isprovided'for the magnetic field by a hollow core 32 made ofalow magneticreluctance material, which is generally an iron based mate rial. Thecore 32, whice is generally made of two adhesively secured togethermirror image parts -32a-32b to permit it conveniently to be mounted inplace on the deflection yoke assembly, defines an open-ended cavity 34therein having a generally forwardly flaring configuration like the mainbody portion 6 of the frame4 and the outermost deflection coils 30a-30bwhich the core envelopes. Unlike the cores used in deflection yokeassemblies heretofore produced wherein the .core snugly fit around theoutermost deflection coils as previously indicated, the core 32 fitsloosely around the latter coils so that it is adjustable relativethereto along at least one axis, most especially the vertical axis, ofthe'deflection yoke assembly, and most advantageously also along thehorizontal axis of the deflection yoke assembly. For example, it wasfound that in most cases sufficient clearance is provided to usefullyadjust'or optimize the beam deflection parameters of the deflection yokeassembly when the permitted movement of the core 32 relative to theouter deflection coils 30a-30b is from about 0.020 to 0.040 inches.

In the particular deflection coil assembly 2 illustrated in FIG. 1, theadjustment of the core position is effected by a core adjusting fixtureto be described into which the deflection yoke. assembly 2 istemporarily placed for adjustment. Following such adjustment, theposition of the core is fixed by application of a suitable adhesive orthe like. (In accordance with another aspect of the invention to bedescribed, the means for adjusting the core is a permanent attachment tothe deflection yoke assembly so that the television manufacturer orrepairman may make an adjustment thereof, if

9 of conductors extending to the various terminals of a standard testtelevision receiver 50 supplied by the television receiver manufacturerto which the deflection coil assembly is to be sold. FIG. 2 illustratesan exemplary adjusting station 51 used at the plant of the deflectionyoke assembly manufacturer. (It should be understood that theconstruction and arrangement of the various components forming part ofthe adjusting station 51 may vary widely.) As there shown, an equipmentsupport rack 52 is provided having a bottom shelf 54 upon which reststhe standard test receiver 50. Supported on an intermediate shelf 58 ofthe rack is a mirror 60 inclining upwardly and rearwardly atapproximately a 45 angle. The mirror 60 is visible easily by a personsitting in front of the rack 52 viewing the same through an opening 61extending to the front margin of an upper shelf 62. The opening 61extends a substantial distance across the width of the shelf 62, andsupported above the rear portion of this opening is the color cathoderay tube 66 used with the standard test receiver. The cathode ray tube66 is mounted with its front side screen-forming end 66a facingdownwardly so that the beam traces appearing on the cathode ray tubescreen will be reflected forwardly by the mirror 60 on the shelf below,so the person making the adjustments to be described can see the beamtraces through the front portion of the opening 61 as he glancesdownwardly and rearwardly upon the mirror 60. The cathode ray tube 66may be confined in this downwardly facing position in any suitable way.For example, the margins of the front face of the cathode ray tube maybe supported upon the defining margins of the shelf opening 61 andconfined in a given position thereover by suitable positioning means,which may include cushion elements 69.

There is supported upon the wide front end 66a of the cathode ray tubeadjacent the neck portion 66b thereof an adjusting fixture 63 (whichwill be described later on in the specification) in which is supportedthe deflection yoke assembly 2. As will be described in more detail, theadjusting fixture 68 has an adjusting member 68a for adjusting theposition of the core 32 relative to the deflection coils 28a-28b anda-30b along the normal vertical axis of the deflection yoke assembly,(the normal horizontal or vertical axis being related to the usualhorizontally oriented position of the deflection yoke assembly upon theneck of a cathode ray tube), and an adjusting member 68b for adjustingthe position of the core 32 along the normal horizontal axis thereof.Positioned behind the deflection yoke assembly 2 around the neck 66b ofthe cathode ray tube 66 is a convergence assembly 72 having the usualstatic convergence adjusting control members 72a, 72b and 720 (FIG. 3).The convergence assembly 72 may have windings (not shown) which receivethe dynamic convergence signals previously referred to. These windingsare connected through various insulated conductors 73 to a connector 75which connects with a complimentary connector 77 connected by a cable 79of conductors to the standard test receiver 50 in a conventional way.Suitable magnet-containing lateral blue width and purity adjustingcontrols 80 and 83 are also supported around the neck 66a of the cathoderay tube behind the convergence assembly 72 in the usual manner. Sincethese controls are not associated directly with any electricalcircuitry, there are no electrical conductors associated therewith. Theplug terminals at the end of the neck of the cathode ray tube areconnected through a socket connector 85 and conductors in a cable 92 tothe standard test receiver 50 in a conventional way.

The adjusting station further includes what is sometimes referred to asa color generator 95 shown mounted on a support shelf extending from oneside of the rack 52. The color generator 95 has a cable 104 extending tothe standard test receiver 50. The color generator 95 is a well knownunit which generates selected voltages fed to the input terminals of thestandard test receiver 50 to effect one of a selected number of videopatterns on the screen of a color television cathode ray tube. Thesevoltages provide synchronization and intensity control voltages in theusual manner to provide the desired pattern on the screen of the cathoderay tube, such as the cross-hatch pattern shown in FIG. 6 to whichreference will be made later on in the specification.

Refer now more particularly to FIGS. 4 and 5 and 5A which shows theconstructional details of an exemplary deflection coil assemblyadjusting fixture 68. As there shown, the fixture includes a base plate106 provided with suitable means for supporting the same upon thedownwardly facing cathode ray tube 66. As illustrated, this meanscomprises spaced supporting legs 108 each having a vertically extendingshank portion 108a secured by a screw 110 passing through a verticallyelongated slot 112 in the shank portion 108a and threading into thethreaded opening in the base plate 106. The position of the base plate106 with regard to the neck portion of the cathode ray tube 66 canthereby be adjusted over certain limits. The shank portion 108a of eachleg 108 terminates in an outwardly and downwardly inclining intermediateportion 108b which bears upon a cushion pad 116 directly bearing on theouter surface of the forwardly flaring front end 66a of the cathode raytube 66. The intermediate portion 10812 of each leg terminates in anoutwardly extending eyeletforming portion 1086 through which extends asecuring wire 120 connected to one end of a turnbuckle 122. or the likewhose opposite end is connected by a wire 123 to an eyelet 124 securedto one of the corners of a cushion 69.

Adjustably mounted upon the top of the base plate 106 is a slide plate126 having parallel elongated guide slots 128 into which pass theunthreaded shank portion of guidepins 130 having ends threading into thebase plate 106. The guidepins 130 guide the slide plate 126 for movementparallel to a reference axis 131. The slide plate 126 has a block 132 towhich the threaded shank portion 133 of a threaded rod 133 is anchored.The adjusting member 68a may include a knurled knob 135 projectingthrough a narrow slot 137 in a block 137 secured to the base plate 106and threaded around the shank of the threaded rod 133 passing throughunthreaded holes in the block 137. Rotation of the knob 135 in onedirection or the other brings the knob against one of the defining wallsof the slot 137 and moves the slide plate 126 in one direction or theother parallel to the axis 131. A screw 134 threaded into the slideplate 126 bears on the surface of the base plate 106 to fix the adjustedposition thereof.

The base plate 106 has a relatively large opening 136 whose definingwalls are in substantial spaced relationship to the adjacent portion ofthe cathode ray tube. The defining walls of the opening 136 are providedwith a stepped deflection yoke assembly positioning rece'ss'defined byan upwardlyfacing annular support surface l38uponwhich the front edgeportion of the an- 'nular skirt of the frame of the deflection yokeassembly rests, and a radially inwardly extending surface 140 againstwhich the side of the annular skirt 10 is snugly positioned. Thedeflection yoke assembly is positioned within this recess of the baseplate 106 so the normal vertical axis of the deflection yoke assembly,which in the illustrated embodiment of the invention is the separationline between the frame parts 4a and 4b .as best shown in FIG. 8, isco-extensive with the axis 131 of theadjusting fixture 68. Thedeflection yoke assembly positioning recess thus fixes the position ofthe .frame and the deflection coils mounted thereon relative to, thecathode ray tube '66. The slide 'platei126 has a central opening 142'ofmuch greater size than theopening 136 in the base plate" 106.]Supp'ortedon diametrically opposite sides of the opening 142 of the slide plate126 in a direction transverse to the aforementioned axis 131 are a pairof guide-forming means l44l44 supporting a slide member 145 carryingcore-engaging jaw members 146-146 for movement parallel to an axis 131transverse to the aforementioned axis 131. The jaw members 146-446, asillustrated, have confronting surfaces l48148 sized and shaped snugly toengage opposite sides of the core 32 of the deflection yoke assembly.The core 32,- as illustrated, has a front cylindrical ing the-jawmembers 146-446 on the ends thereof.

This linkage ,is anchored to and carried by the slide member 145 fittinginto an opening in the slide plate 126. The slide member 145 has aring-shaped center portion 145a with a large center opening 155. Theringshaped center portion 145a terminates in opposite end portionsl45b-l45b which are slidably mounted within guideways of theguide-forming means l44-l44. The slide member 145 is adjustable alongthe aforementioned axis 131' by the aforementioned adjusting member 68bwhich, as illustrated, is similar to-adjusting member 68a by including aknurled knob 157 projecting through a narrow slot 158' in a block 158 onthe base plate and threaded around the shank 157' of a threaded rod 157passing through unthreaded holes in the block 158 and anchored to theslide member 145. Thus, rotation of the knurled knob 157 in onedirection or the other advances the slide member 145 in onedirection orthe other parallel to the axis 131'. A'screw l59-threaded into the slidemember 145 and bearing on thesurface of the base plate 106 locks theslide member into its adjusted position. It should be apparent that withthe adjusting fixture 68 above described, the core 32 is independentlyadjustable along two orthogonal axes. I

Either after or before the deflection yoke assembly 2 is positionedwithin the adjusting fixture 68, the outermost deflection coils 30a -30bare adjusted so the cross-coupling therebetween (commonly referred to ascross talk) is reduced substantially to zero using conventional voltagemeasuring techniques, and the zero cross talk position of the outermostdeflection coils is fixed by applying a suitable adhesive between theoutermost deflection coils and adjacent exposed portions of the frame 4in the conventional manner. If it is believed necessary to make asubsequent cross talk adjustment after other parameters of thedeflection yoke assembly are adjusted in the manner to be described, theadhesive is applied in a manner or is one which remains fairly soft overthe period involved, so that the adhesive can be easily removed orbroken to make a further adjustment of the outermost deflection coilsfollowing which additional adhesive is added to permanently affix theposition of the outermost deflection coils. g I

In accordance with the invention the deflection yoke assembly ispositioned in the adjusting fixture 68 in the manner previouslydescribed so that rotation of the adjusting member 68a thereof will movethe core 32 relative to the deflection coils along the normal verticalaxis of the deflection yoke assembly and the rotation of the adjustingmember 68b will move the core 32 rela tive to the deflection coils alongthe normal horizontal axis of the deflection yoke assembly. Before thisadjustment is made, the usual purity and static convergence adjustmentsare made by the controls 72a, 72b, 72c, and 83 (FIG. 3) with the propersignals applied to and by the standard test receiver 50 in a well knownmanner (which will'not be here described), with no dynamic convergencesignals applied to the convergence assembly 72. (This can beaccomplished by using a convergence assembly without the dynamicconvergence signal-receiving windings or by eliminating the conductorsnormally connecting with. such windings from the cable 79.

in accordance with the most preferred procedure for utilizing theadjustable core feature of .the present invention, after the abovereferred to.cross talk, purity and static convergence adjustments aremade, the color generator is set (if not previously so set) so that itproduces a conventional cross-hatch pattern as shown in FIGS. 6, 7Aand'7B. In such a pattern, all of the colored beams are energized toproduce a cross grid pattern of adjacent red, green and blue tracesrespectively identified by the reference characters R, G and B. FIGS. 7Aand 7B show in magnified form the various color traces at the l2, 3, 6and 9 oclock positions P1, P2, P3 and P4 on the face of the screen ofthe cathode ray tube, and also at the center and four corner positionsP5, P6, P7, P8 and P9 thereof. In FIG. 7A, the solid arrows illustratethe direction of movement of the red, green and blue traces when theadjusting member 68a is adjusted in a direction which moves the core 32in a normal upward direction along the normal vertical axis of thedeflection yoke assembly and the dashed arrows therein indicate thedirection of movement of the various traces when the adjusting member68a is moved in a direction to move the core 32 in a normal downwarddirection along the normal vertical axis of the deflection yokeassembly. In FIG. 7B, the solid arrows illustrate the direction ofmovement of the red, green and blue traces R, G and B when the adjustingmember 68b is adjusted in a direction with moves the core 32left alongthe normal horizontal axis of the deflection yoke assembly and thedashed arrows therein indicate the opposite direction of movement of thevarhorizontally extending green trace so it is rotated a substantialdegree with respect thereto in a counterclockwise direction as seen inthe drawings. As previously indicated, in accordance with the invention,the deflection parameters of the deflection coil assembly are optimizedto a substantial degree by moving the adjusting member 68a in adirection which will rotate the horizontally extending red trace closerto, and in most cases preferably in alignment with, the horizontallyextending green trace, thereby producing a horizontal yellow line acrossthe center of the screen of the cathode ray tube. The televisionreceiver manufacturer will commonly specify the maximum permissibledegree of red trace crossover at the 3 and 9 oclock positions of thecross-hatch pattern.

While this adjustment in presently manufactured deflection yokeassemblies may be sufficient in most instances to optimize thedeflection producing parameters of the deflection yoke assembly, in themost advantageous form of the present invention another adjustment ismade with the adjusting member 68b which affects the horizontallyextending red and green traces R and G at the 12 and 6 oclock positionsP1 and P3 of the cross-hatch pattern. It will be noted in FIGS. 7A and78 that at the 12 oclock position Pl, the horizontally extending redtrace R crosses the horizontally extending green trace G at a point tothe left of the point where the centered vertical blue trace B passesthrough the green trace G, so the red trace is above the green trace atthe centered vertical blue trace B. In contrast to this, at the 6 oclockposition P3, the horizontally extending red trace R crosses thehorizontally extending green trace G at a point far to the right of thepoint where the centered vertical blue trace B passes through the greentrace G, so the red trace is below the green trace at the centeredvertical blue trace B by an amount greater than the spacing of thehorizontally extending red trace R from the horizontal green trace Galong the vertical blue trace B passing through the green trace G at the12 oclock position Pl. There is present what is referred to as anunequal red raster height. in accordance with another aspect of theinvention, the beam deflection parameters of the deflection yokeassembly are further optimized by rotating the adjusting member 68b soas to move the core along the normal horizontal axis of the deflectionyoke assembly to equalize the red raster height at the 12 and 6 oclockpositions P1 and P3 of the cross-hatch pattern. This adjustment movesthe horizontally extending red traces R at the 12 and 6 oclock positionsin opposite directions relative to horizontally extending green traces Gat these points. It is preferable that this equalized position be onewherein the raster height at the point where the horizontally extendingred and green traces cross the centered vertical blue traces B at the 12and 6 oclock positions to produce a zero red raster height, but this isfrequently not possible. However, an equalization of this red rasterheight is what is important to effect the best adjustment of thedeflection coil assembly.

The core 32 is most advantageously provided with a number of widelyspaced apertures 159 (see FIGS. 8 and 9) at points overlying theoutermost deflection coils 30a and 30b, and these apertures are filledwith a hot-melted adhesive 160 so as to fix the adjusted position of thecore 32 with regard to the deflection coils. As the hot melt cools,which may take from about 30 seconds to 1 minute, the effect of thevarious adjustments at the 12, 3, 6 and 9 oclock positions P1, P2, P3and P4 of the cross-hatch pattern are checked to be sure that theseadjustments are maintained.

Following the aforementioned adjustment, measurements are made of thehorizontal separation of the vertical blue traces B from the verticalgreen traces G at the 3 and 9 oclock positions P2 and P4 (referred to asblue width) to see if they meet specifications and, if not, thedeflection yoke assembly is sent to the repair section for a coilchange. Similarly, what is referred to as the reverse trap (dealing withthe relative overall height of the vertical red and green traces R and Gat the left and right sides of the cross-hatch pattern) is checked alongwith the spacing of the colored beams at the corners P6, P7, P8 and P9of the cross-hatch pattern to determine whether the various beam spacingspecifications set by the television receiver manufacturer are met and,if not, the deflection yoke assembly is similarly sent to the repairsection for coil replacement.

Refer now to FlGS. l0 and 11 which illustrate a modified form ofdeflection yoke assembly 2 wherein the deflection yoke assembly includesas a permanent attachment thereofa deflection yoke assembly adjustingstructure 68 permitting adjustment by the television receivermanufacturer or television repairman. (Many of the parts of thestructure 68' correspond in function to portions of the deflection coilassembly adjusting fixture 68 previously described, and thecorresponding elements therein have been similarly numbered, with aprime used on the parts of the structure 68. The structure 68 includesan inner stationary annular plate 106' secured in any suitable way tothe wall 12 of the insulating frame 4' of the deflection coil assembly2. The inner annular plate 106 has a central opening 161 which fitsloosely around the narrow cylindrical inner end 150 of the core 32 sothe position of the core is radially adjustable with respect to theannular plate 106'. The inner annular plate 106 has an outwardly axiallyextending ear 163 having a slot 165 extending therethrough. At a pointon the periphery of the inner annular plate 106 diametrically oppositethe ear 163 there is provided an outwardly axially extending lug 167having a circular hole 167' therein. Projecting axially outwardly fromthe inner annular plate 106 at diametrically opposite points on theannular inner plate 106 and transversely to the spacing of the ear 163and lug 167 are a pair of guide tongues 168-168.

Supported adjacent the outer face of the inner annular plate 106 is anannular slide plate 126 which is slidably mounted with respect to theinner annular plate 106 along an axis extending between theaforementioned ear 163 and the lug 167. To this end, the annular slideplate 126 has a tongue 169 extending radi ally therefrom which isslidably disposed within the slot 165 in the ear 163 on the innerannular plate 106. The

' annular slide plate 126 is also provided with a pair ofdiametricallyoppositely disposed elongated guide slots guide the annularslide plate 126' formovement in the direction of the length of theslots. The annular slide plate 126' has an ear 171 positioned adjacenttov the inner side of the aforementioned lug, 167, the ear 171 having'ahole 171' in alignment with the aforesaid lug hole 167 An adjustingmember 68a is provided including a hollow hub portion 173 forming aknurled knob in which is anchored the reduced unthreaded portion 172' ofa screw 172 threading within the hole 171 The unthreaded portion 172 ofthe adjusting member 68a is rotatable within the hole 167' of the lug167, the defining walls of which form a bearing for the screw 172. Whenthe screw is rotated in one direction or the other the annular slideplate 126' is moved along the face-of the annular inner plate 106 whichit confronts in a direction parallel to the elongated guide slots170-170 in the annular slide plate 126'.

Adjustably mounted upon the slide plate 126' is a core mountedannularplate 154 which has a pair of diametrically oppositely disposedelongated guide slots 177-177 which fit over relatively narrow guidextongues175-175 projecting axially outwardly from the outer face of theslide plate 126. The guide tongues 175-175 have a thicknessapproximately equal to the width of the slots 177-177 and a length muchless than the length thereof, so that the guide tongues 175-175 guidethe core connected annular plate 154 for movement in the direction ofthe length of the slots 177-177, which is transverse to the direction inwhich the slide plate 126 is slidable relative to the inner annularplate 106'. v a

The slide plate 126' is provided with an outwardly axially extending lug180 which has a hole 181 for rotatably supporting the reducedunthreadedportion 182' of a screw 182 forming part of an adjusting means 68b. Thescrew 182 extends into and is anchored to a hollow hub 183 forming aknurled knob. The core connected annular plate 154' has an outwardlyaxially extending lug 186 positioned in confronting spaced relationship"to the inner side of the lug 180 on the slide plate 126.

The lug 184 has a threaded opening 186 in which the screw 182 isthreaded. It is thus apparent that upon rotation of the knurled hub 183from which the screw 182 extends, the core connected annular plate 154'will move along the slide plate 126' which it confronts in a directionparallel to the length of the guide slots 177-177 therein.

The core connected annular plate 154' anchored to the core 32' of thedeflection coil assembly 2 by means of a clamping member 148' which is asplit sleeve-like structure firmly secured around the cylindrical innerend 150' of the core by a clamping screw 187.

The clamping member 148 is secured to the core connected annular member154' by means including axially extending legs 188-188 terminating inradially outwardly extending flanges 190-190 abutting a pair of radialwings 192-192 extending from the clamping member 148'. The flanges190-190 have holes 198-198 aligned with holes 200-200 on the wings192-192. Bolts 204-204 passing through the aligned pairs of holes198-200 and nuts 206-206 threading around the bolts 204-204 interconnectthe flanges 190-190 and the wings 192-192.

It is apparent that the modified deflection coil assem- 1 bly 2' withthe integral adjusting structure 68' may be adjusted in the same mannerpreviously described in connection with the adjustment of the deflectioncoil assembly 2, to provide the proper relationship between the beamdeflecting parameters of the deflection coil assembly 2. An adjustingstation similar to that shown in FIG. 2 may be provided for this purposeand the identical procedure carried out as previously described.

It should be understoodthat numerous modifications may be made in theprocedures for adjusting the deflection coil assembly described abovewithout deviating from the broader aspects of the invention.

1 claim:

1. A method of manufacturing a deflection yoke assembly with optimizedbeam deflecting parameters permitting the beams of a color televisioncathode ray tube to be properly dynamically converged over the face ofthe cathode ray tube, said method comprising: fabricating the deflectionyoke assembly so it includes a frame mountable around the neck ofa-color television cathode ray tube, the frame supporting vertical andhorizontal deflection coils and a core related to said vertical andhorizontal deflection coils to form a low reluctance path for themagnetic field outside the neck of the cathode ray tube, one of saidcore and deflection coils being mounted for fine adjustment with respectto the other of same parallel to at least one of the horizontal andvertical axes of the deflection yoke assembly, mounting the deflectionyoke assembly on the neck of a standard test color television cathoderay tube including beam intensity control terminals for controlling theintensity of the electron beams thereof striking the cathode ray tubescreen, mounting purity and static convergence apparatus mounted aroundthe neck of said cathode 'ray tube, making the usual purity and staticconvergence adjustments with said apparatus and, while applying signalsto said cathode ray tube control terminals and to one of said horizontaland vertical deflection coils of said deflection yoke assembly toproduce colored horizontal beam traces to be converged at least at twopoints spaced on opposite sides of the center point of the screen,adjusting the relative position between the core and at least one ofsaid horizontaland vertical deflection coils to produce the desiredconvergence of said horizontal beam traces at said points.

2. The method of claim 1 wherein the horizontal and vertical deflectioncoils are immovably mounted relativeto said frame, and said adjustingoperation is performed by moving the core.

3. The method of claim 1 wherein said deflection yoke assembly frame isheld in a fixed position and said core is clamped to a finely adjustablesupport structure which supports the core for movement along said axis.

4. The method of claim 3 wherein said adjustable structure includesmeans for holding said deflection yoke assembly frame in a fixedposition, said frame and holding means forms a re-usable assembly whichis only temporarily attached to the deflection yoke assembly, the corebeing adhesively secured in place on the deflection yoke assembly frameafter said adjustment thereof is made.

5. A method of manufacturing a deflection yoke assembly with optimizedbeam deflecting parameters permitting the beams of a color televisioncathode ray tube to be properly dynamically converged over the face ofthe cathode ray tube, said method comprising: fabricating the deflectionyoke assembly so it includes a frame mountable around the neck of acolor television cathode ray tube, the frame supporting vertical andhorizontal deflection coils and a core related to said vertical andhorizontal deflection coils to form a low reluctance path for themagnetic fields outside the neck of the cathode ray tube, one of saidcore and horizontal deflection coils being mounted for fine adjustmentwith respect to the other of same parallel to the vertical axis of thedeflection yoke assembly, mounting the deflection yoke assembly on theneck of the standard test color television cathode ray tube includingbeam intensity control terminals for controlling the intensity of theelectron beams thereof striking the cathode ray tube screen, mountingpurity and static convergence apparatus around the neck of said cathoderay tube, making the usual purity and static convergence adjustmentswith said apparatus and, while applying signals to said cathode ray tubecontrol terminals and at least to said horizontal deflection coils ofsaid deflection yoke assembly to produce at least across the horizontalcenter band of the screen of the cathode ray tube colored horizontalbeam traces, adjusting the relative vertical position between said coreand horizontal deflection coils to produce a desired degree ofconvergence between at least two of the horizontal traces along saidcenter band of said cathode ray tube screen at the 3 and 9 oclockpositions thereof.

6. The method of claim 5 wherein said adjusting operation is made toproduce a zero or near zero convergence between the horizontal red andgreen traces at the 3 and 9 oclock positions of the cathode ray tubescreen.

7. The method of claim 5 wherein the horizontal and vertical deflectioncoils are immovably mounted relative to said frame, and said adjustingoperation is performed by moving the core.

8. The method of claim 5 wherein said deflection yoke assembly frame isheld in fixed position and said core is clamped to a finely adjustablesupport structure which supports the core for movement along said axis.

9. The method of claim 8 wherein said adjustable structure includesmeans for holding said deflection yoke assembly frame in a fixedposition, said frame and holding means forms a re-usable assembly whichis only temporarily attached to the deflection yoke assembly, the corebeing adhesively secured in place on the deflection yoke assembly frameafter said adjustment thereof is made.

10. A method of manufacturing a deflection yoke assembly with optimizedbeam deflecting parameters permitting the beams of a color televisioncathode ray tube to be properly dynamically converged over the face ofthe cathode ray tube, said method comprising: fabricating the deflectionyoke assembly so it includes a frame mountable around the neck of acolor television cathode ray tube, the frame supporting vertical andhorizontal deflection coils and a core related to said vertical andhorizontal deflection coils to form a low reluctance path for themagnetic fields outside the neck of the cathode ray tube, one of saidcore and vertical deflection coils being mounted for fine adjustmentwith respect to the other of same parallel to the horizontal axis of thedeflection yoke assembly, mounting the deflection yoke assembly on theneck of a standard test color television cathode ray tube including beamintensity control terminals for controlling the intensity of theelectron beams thereof striking the cathode ray tube screen, mountingpurity and static convergence apparatus around the neck of said cathoderay tube, making the usual purity and static convergence adjustmentswith said apparatus and, while applying signals to said cathode ray tubecontrol terminals and to said horizontal and vertical deflection coilsof said deflection yoke assembly to produce at least across theuppermost and lowermost portions of said screen of the cathode ray tubecolored horizontal beam traces, adjusting the relative horizontalposition between said core and vertical deflection coils to produce adesired degree of convergence between at least two of the horizontaltraces at the 12 and 6 oclock positions of the cathode ray tube screen.

Ill. The method of claim 5 wherein said adjusting operation is made toproduce a substantially equal spacing between the horizontal red andgreen traces at the 3 and 9 oclock positions of the cathode ray tubescreen.

12. The method of claim 11 wherein said signals produce also across thehorizontal center band of the cathode ray tube screen colored horizontaltraces, the adjustable one of said core and deflection coils is mountedfor independent adjustment respectively along the horizontal andvertical axes of the deflection yoke assembly, and the adjustable one ofsaid core and horizontal deflection coils is also adjusted along saidvertical axis to produce zero or near zero convergence between thehorizontal red and green traces at the 3 and 9 oclock positions of thecathode ray tube screen.

15. The method of claim 14 wherein said adjustable structure includesmeans for holding said deflection yoke assembly frame in a fixedposition, said frame and holding means forms a re-usable assembly whichis only temporarily attached to the deflection yoke assembly, the corebeing adhesively secured in place on the deflection yoke assembly frameafter said adjustment thereof is made.

1. A method of manufacturing a deflection yoke assembly with optimizedbeam deflecting parameteRs permitting the beams of a color televisioncathode ray tube to be properly dynamically converged over the face ofthe cathode ray tube, said method comprising: fabricating the deflectionyoke assembly so it includes a frame mountable around the neck of acolor television cathode ray tube, the frame supporting vertical andhorizontal deflection coils and a core related to said vertical andhorizontal deflection coils to form a low reluctance path for themagnetic field outside the neck of the cathode ray tube, one of saidcore and deflection coils being mounted for fine adjustment with respectto the other of same parallel to at least one of the horizontal andvertical axes of the deflection yoke assembly, mounting the deflectionyoke assembly on the neck of a standard test color television cathoderay tube including beam intensity control terminals for controlling theintensity of the electron beams thereof striking the cathode ray tubescreen, mounting purity and static convergence apparatus mounted aroundthe neck of said cathode ray tube, making the usual purity and staticconvergence adjustments with said apparatus and, while applying signalsto said cathode ray tube control terminals and to one of said horizontaland vertical deflection coils of said deflection yoke assembly toproduce colored horizontal beam traces to be converged at least at twopoints spaced on opposite sides of the center point of the screen,adjusting the relative position between the core and at least one ofsaid horizontal and vertical deflection coils to produce the desiredconvergence of said horizontal beam traces at said points.
 2. The methodof claim 1 wherein the horizontal and vertical deflection coils areimmovably mounted relative to said frame, and said adjusting operationis performed by moving the core.
 3. The method of claim 1 wherein saiddeflection yoke assembly frame is held in a fixed position and said coreis clamped to a finely adjustable support structure which supports thecore for movement along said axis.
 4. The method of claim 3 wherein saidadjustable structure includes means for holding said deflection yokeassembly frame in a fixed position, said frame and holding means forms are-usable assembly which is only temporarily attached to the deflectionyoke assembly, the core being adhesively secured in place on thedeflection yoke assembly frame after said adjustment thereof is made. 5.A method of manufacturing a deflection yoke assembly with optimized beamdeflecting parameters permitting the beams of a color television cathoderay tube to be properly dynamically converged over the face of thecathode ray tube, said method comprising: fabricating the deflectionyoke assembly so it includes a frame mountable around the neck of acolor television cathode ray tube, the frame supporting vertical andhorizontal deflection coils and a core related to said vertical andhorizontal deflection coils to form a low reluctance path for themagnetic fields outside the neck of the cathode ray tube, one of saidcore and horizontal deflection coils being mounted for fine adjustmentwith respect to the other of same parallel to the vertical axis of thedeflection yoke assembly, mounting the deflection yoke assembly on theneck of the standard test color television cathode ray tube includingbeam intensity control terminals for controlling the intensity of theelectron beams thereof striking the cathode ray tube screen, mountingpurity and static convergence apparatus around the neck of said cathoderay tube, making the usual purity and static convergence adjustmentswith said apparatus and, while applying signals to said cathode ray tubecontrol terminals and at least to said horizontal deflection coils ofsaid deflection yoke assembly to produce at least across the horizontalcenter band of the screen of the cathode ray tube colored horizontalbeam traces, adjusting the relative vertical position between said coreand horizontal deflection coils to produce a desired degree ofcoNvergence between at least two of the horizontal traces along saidcenter band of said cathode ray tube screen at the 3 and 9 o''clockpositions thereof.
 6. The method of claim 5 wherein said adjustingoperation is made to produce a zero or near zero convergence between thehorizontal red and green traces at the 3 and 9 o''clock positions of thecathode ray tube screen.
 7. The method of claim 5 wherein the horizontaland vertical deflection coils are immovably mounted relative to saidframe, and said adjusting operation is performed by moving the core. 8.The method of claim 5 wherein said deflection yoke assembly frame isheld in fixed position and said core is clamped to a finely adjustablesupport structure which supports the core for movement along said axis.9. The method of claim 8 wherein said adjustable structure includesmeans for holding said deflection yoke assembly frame in a fixedposition, said frame and holding means forms a re-usable assembly whichis only temporarily attached to the deflection yoke assembly, the corebeing adhesively secured in place on the deflection yoke assembly frameafter said adjustment thereof is made.
 10. A method of manufacturing adeflection yoke assembly with optimized beam deflecting parameterspermitting the beams of a color television cathode ray tube to beproperly dynamically converged over the face of the cathode ray tube,said method comprising: fabricating the deflection yoke assembly so itincludes a frame mountable around the neck of a color television cathoderay tube, the frame supporting vertical and horizontal deflection coilsand a core related to said vertical and horizontal deflection coils toform a low reluctance path for the magnetic fields outside the neck ofthe cathode ray tube, one of said core and vertical deflection coilsbeing mounted for fine adjustment with respect to the other of sameparallel to the horizontal axis of the deflection yoke assembly,mounting the deflection yoke assembly on the neck of a standard testcolor television cathode ray tube including beam intensity controlterminals for controlling the intensity of the electron beams thereofstriking the cathode ray tube screen, mounting purity and staticconvergence apparatus around the neck of said cathode ray tube, makingthe usual purity and static convergence adjustments with said apparatusand, while applying signals to said cathode ray tube control terminalsand to said horizontal and vertical deflection coils of said deflectionyoke assembly to produce at least across the uppermost and lowermostportions of said screen of the cathode ray tube colored horizontal beamtraces, adjusting the relative horizontal position between said core andvertical deflection coils to produce a desired degree of convergencebetween at least two of the horizontal traces at the 12 and 6 o''clockpositions of the cathode ray tube screen.
 11. The method of claim 5wherein said adjusting operation is made to produce a substantiallyequal spacing between the horizontal red and green traces at the 3 and 9o''clock positions of the cathode ray tube screen.
 12. The method ofclaim 11 wherein said signals produce also across the horizontal centerband of the cathode ray tube screen colored horizontal traces, theadjustable one of said core and deflection coils is mounted forindependent adjustment respectively along the horizontal and verticalaxes of the deflection yoke assembly, and the adjustable one of saidcore and horizontal deflection coils is also adjusted along saidvertical axis to produce zero or near zero convergence between thehorizontal red and green traces at the 3 and 9 o''clock positions of thecathode ray tube screen.
 13. The method of claim 10 wherein thehorizontal and vertical deflection coils are immovably mounted relativeto said frame, the said adjusting operation is performed by moving thecore.
 14. The method of claim 13 wherein said defleCtion yoke assemblyframe is held in a fixed position and said core is clamped to a finelyadjustable support structure which supports the core for movement alongsaid axis.
 15. The method of claim 14 wherein said adjustable structureincludes means for holding said deflection yoke assembly frame in afixed position, said frame and holding means forms a re-usable assemblywhich is only temporarily attached to the deflection yoke assembly, thecore being adhesively secured in place on the deflection yoke assemblyframe after said adjustment thereof is made.